Modern motor vehicles, and particularly off-highway vehicles, are designed using automatic ride height controls, so as, for instance, to compensate for level differences caused by street or terrain unevenness. To do this, the ride height control includes regulating units, for adapting the level position of a motor vehicle, which, for example, are designed as air springs and are driven by a compressor. In addition, the ride height control includes inclination and/or distance sensors for recording the distance to the roadway foundation. The data of this sensor technology are evaluated by a control unit, and the compressor is driven such that it activates the air springs so that a level position set as the setpoint value is adjusted to. At higher level positions the problem arises that the center of gravity of the motor vehicle is shifted upwards. At higher motor vehicle speeds, this in turn leads to a stability problem, so that there is the danger of rollover of the motor vehicle. To avoid this problem, the automatic ride height control records the motor vehicle speed, and when a boundary speed is exceeded, it automatically adjusts to a lower level, in order to achieve again a sufficient stability.
In the conventional automatic ride height controls it is a disadvantage that the compressors are frequently stressed unnecessarily, which lowers the service life of the compressors and generally the activating members of the regulating units, and represents unnecessary noise pollution for the driver.
It is therefore an object of the present invention to provide a method and a device for the automatic ride height control for a motor vehicle, by which the activating members of the regulating units are less strongly stressed.